BIOL 331 Lecture Notes - Lecture 33: Dna-Binding Domain, Glucocorticoid Receptor, Transactivation
Document Summary
Steroid hormones can enter the cell and bind their receptor in the cytoplasm. Ligands of steroid hormones are lipid soluble. Steroid hormones are already in the cytoplasm. Cytoplasmic receptors can directly control gene expression by travelling to the nucleus and binding dna, recruiting coactivators or copressors. Dna binding domain binds to specific dna sequences in promoter. Steroid hormone receptors have a ligand-binding domain to activate the receptor. Has the potential of being a transcription factor. Receptor and cortisol enter the nucleus and attach on dna. Receptor and cortisol can activate or repress gene transcription based on which proteins are present. Gr interacts with chromatin to regulate transcription. Example: thyroid hormone receptor, retinoic acid receptors, estrogen receptors, etc. Receptor binds ligand in the cytoplasm and together they go to the nucleus to activate transcription. Active gr binds to dna and recruits coactivators (cbp) Acetylated histones recruit chromatin remodellers (swi/snf), which create docking sites for extra proteins.